From: Robert Klemme <shortcutter@...>
Date: 2009-03-19T18:37:22+09:00
Subject: Re: Wrapping applications in Ruby

On 19.03.2009 10:02, Jp Hastings-spital wrote:
> Dylan Evans wrote:
>> I won't go into details but you should look into pipes in this case.
> 
> Thanks for the prompt response - I'm assuming you mean Ruby pipes not 
> BASH pipes or equivalent. (http://www.ruby-doc.org/core/classes/IO.html)
> 
> I'll post here if I find a solution.

I have no idea what you mean by "bash pipes" but the underlying 
mechanism is the same.  It's a feature of the operating system.  One 
solution is to use IO.popen.  Your code does not read all the lines, 
that might be one reason for your issue.

robert@fussel /c/Temp
$ ./run-counter.rb
Got 0
Got 10
Got 20
Got 30
Got 40
Got 50
Got 60
Got 70
Got 80
Got 90
Got 100

robert@fussel /c/Temp
$ cat run-counter.rb
#!/usr/bin/env ruby19

IO.popen "./counting.rb" do |io|
   io.each do |line|
     pct = line[%r{:\s*(\d+)%}, 1].to_i
     puts "Got #{pct}"
   end
end

robert@fussel /c/Temp
$ cat counting.rb
#!/usr/bin/env ruby19

$stdout.sync = true

11.times do |n|
   puts "Completed: #{n*10}%"
end

robert@fussel /c/Temp
$

Similar with Open3, only that you then get multiple pipes.

Cheers

	robert

-- 
remember.guy do |as, often| as.you_can - without end